Pioneer 8" BOFU BIB

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Pics of BOFU

Hopefully I have attached a picture correctly. The cabinets are not well finished as you can see. They have been made in the factory where I work in Indonesia. (We are not speaker builders!) I have been adjusting 'height' of speakers (30mm adjustment), but I must confess that I cant pick difference.
The most impressive aspect is midrange. Vocals are great. Not sure how to describe bass? It is 'there' whenever present in the music, reasonably extended, but home movie specialists would still require a sub woofer.
I have a very simple setup at the moment. An old Denon PMA1080R amp and Dell M3800 playing FLAC through VLC.
Hope to upgrade my source soon but limited hifi equipment where I live.
 

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BIBs sound much fuller in corners. Without corners they can sound thin. The corner completes the system. They also appear shorter than they should.

Thanks for your comments. The boxes (without bases) are 74.5" tall? I can trial them in another room in corners but still with 11' ceilings when I return from overseas. (They were originally going in corners in our house in Australia.)
I was not aware that the box needed to be close to the ceiling-our Australian house has 12' ceilings. Is there any benefit in extending the horn shape closer to the roof?
 
The ~ 'standard' is ~1 ft gap, though the smaller the room/greater its gain curve down low, the greater it can be, but never having done any experimenting I don't know how much, just that with obviously short lines it must be floor loaded [iBIB], so all things considered, this is what I recommend you experiment with.

GM
 
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You can try putting them upside down with 1 foot legs inside each corner? A bit late for that?

In many cases the "ideal" -in the corner with low ceiling can be a bit boomy, needs lots of damping in my experience,
I've found them to work pretty well with either arounds 1' to the ceiling -or floor ;) OR with more space above- but in the corners


Although this doesn't help you since the high ceilings are the issue, I've always thought they might work well covered with Gypsum board (Sheetrock) and incorporated into the wall (attached to the wall but extending outward like short walls that don't quite reach the ceiling) plastered and painted to match.
 
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Should work fine; the ones I did were baffles across a corner, making the walls the other two sides. Very space efficient and radiated like a corner horn with the exception that I made them full height with the driver and vent at different locations depending on whether the XO was at 120, 350 or 500 Hz max.

If I'm able to build another big system, then I'm going back to this for the subs and use 80 Hz Synergy concept horns for the rest.

GM
 
Hi Guys,

I am interested in making my very first pair of DIY speakers. I am looking at the Pioneer BOFU clone, the GRS 8' Full range. I found 2 designs which look doable for a newbie like me. One is the Nelson Pass BOFU TL box, the other is GM's ML-TL "Max Flat".

I guess GM designed Max Flat specifically for the GRS 8', so the Max Flat should be fail proof. But what about the Pass TL? Is it still suitable for the GRS 8'?

Thanks in advance.
 
Yeah, worse, they used a foam surround that dissolves to a fine powder in my locale, so now have a box full of non functioning ones. :(

GM


Hello GM,


I wanted to share with everyone what I did a few weeks ago. I bought a bunch of BOFU's when they were on sale at PE. I blew one of the speakers one night when my friends were over and we were blasting my ceiling speakers. I fixed it and it sounds great. I sent away to eBay for rubber surrounds.

2Pcs 8'' Speaker Surround Decorative Circle Repair Rubber for Bass Woofer Horn | eBay

Removing the old foam was easier with a heat gun, when the cone was clean I raised the cone with paper towels folded between it and the basket. The dust cap was already removed because I made phase plugs. I spaced the coil with paper to center the cone. I glued the with rubber cement the surround to the cone and let dry then later to the basket. It was easier than I thought. I'm going to buy from the ebay seller more surrounds and gaskets for the ones I have in boxes. I hope you give it a try, it should not dissolve even in your part of the country.
smile.gif
Here are a few pics.

Webber
 

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